In this study, various austenitizing temperatures were selected to explore their influence on the microstructure and mechanical properties of Cr–Mo–Ni–V steels. The dissolution of primary carbides during the quenching process and the precipitation behavior of carbides during the tempering process for the steels were investigated using SEM and EDS analyses. As the austenitizing temperature increases from [Formula: see text]C to [Formula: see text]C, VC can be dissolved into the matrix, and the pinning effect of VC on prior austenite grains is weakened. The dissolved V in the quenched condition has a retarding effect on the carbide precipitation upon tempering. With the austenitizing temperature increasing, both tensile strength and elongation of tempered steels are increased, as well as the impact toughness.

Using NiCl2 and NaOH as raw materials, stacked Ni(OH)2 hexagonal nanoplates with different edge lengths were prepared in a large scale by a simple hydrothermal route. The stacked Ni(OH)2 structure was composed of a certain amount of parallel Ni(OH)2 hexagonal nanoplates along the (001) direction. Each parallel Ni(OH)2 nanoplate had a single-crystal structure, and the exposed planes were (001), (00−1), and (100). The formation mechanism of the stacked Ni(OH)2 structures was discussed on the basis of the Ni(OH)2 crystal structure.